Impact of Tyrosine Kinase Inhibitor Starting Dose on Outcomes in Patients With Non-Small Cell Lung Cancer

Abstract

Background: Epidermal growth factor receptor (EGFR) and anaplastic lymphoma kinase (ALK) tyrosine kinase inhibitors (TKIs) can cause intolerable adverse events in patients with non-small cell lung cancer (NSCLC) and may be prescribed at a lower dose. Objective: Our objective was to analyze the starting doses of oral EGFR and ALK TKIs in patients diagnosed with NSCLC at our institution. Methods: We conducted a retrospective chart review with patients on EGFR and ALK TKIs for NSCLC. Patients were categorized into 2 groups: patients initiated on Food and Drug Administration (FDA) standard dose (SD) and patients initiated on a reduced dose (RD). Progression-free survival (PFS), overall survival (OS) and other treatment outcomes were compared between both groups. Results: Ninety patients were included for analysis. The median time-to-progression for the SD group (n = 67) and RD group (n = 23) were 13.4 months (95% confidence interval [CI]:8.9-15.6) and 15.1 months (95%CI: 5.6-21.5), respectively. Median time-to-death was not estimable for OS. The predicted OS probability at approximately 15 months post treatment initiation for the SD group and RD group was 81.8% and 80.5%, respectively. Conclusion: Patients who initiated TKI therapy at a RD did not have different PFS and 15-month survival outcomes than patients who initiated TKI therapy at the FDA SD.